Amazon Frogbit: Care, Propagation, & More!

Amazon Frogbit (Limnobium laevigatum) is a beautiful medium size floating aquarium plant that has become very famous in recent years. This plant is probably the most beautiful floating plant you can grow on the surface of your tank. It’s green smooth and lush green leaves and beautiful long roots will make your tank look like a piece cut out of the Amazon river. This plant is also known by other names like West Indian Spongeplant, South American Spongeplant, Smooth Frogbit, or simply as Sponge plant. 

We prepared this comprehensive guide to walk you through all the information you need to properly care for Amazon Frogbit long-term. The table of content below can help you jump to the section you need the most.

Overview

Amazon Frogbit is native to tropical and subtropical regions of Central and South America. Because of its beautiful leaves, this plant became famous among aquarium owners in North America. Now after many years of keeping them in aquariums, some frogbits have made their way to the rivers and bodies of water in California and other places in the USA. 

They survive winters in USDA plant zones 8 to 10 which makes them hardy plants. They are flowering plants that produce a white yellow flower and produce seeds. Seeds are toxic if ingested by humans. 

Amazon Frogbit grows slower than other surface floating plants which makes them easy to maintain and control their population. At the same time, they are easy to care for and they do not demand a lot from you. This puts them on the list of easy and beginner-friendly aquarium plants. 

Appearance

Amazon Frogbit

Amazon Frogbit is a medium size plant whose leaves measure about 1 to 1.5 inches in diameter. They grow leaves from a central stem and expand on the water like a flower. They continually grow new leaves from the center and the older leaves usually die after some time.

The leaves of amazon frogbit are thick and round with lush green color. The leaves are very smooth and lack any vein structure or visible pattern. 

The underneath side of the leaves has a whitish-spongy structure that traps the air inside. This is why they are also called sponge plants by some. This sponge structure helps the plant to stay floating on the surface of the water. 

They also shoot new stems that will grow leaves and become new plants. We will discuss this later in detail in the propagation section of this article. 

As mentioned in the Overview section, the Amazon Frogbits are flowering species that grow small white flowers from time to time. The flowers will only last for a few days before they die. but they rarely produce flowers in an aquarium environment. When they flower, the flower is so tiny that it is super hard to see with the naked eye. 

They grow long but fragile roots that can reach 8 – 10 inches. Roots are very soft and fine that some fish might feed on. Fast-moving waters will easily break their leaves and might even drown the entire plant. So it is important to have them in a still tank.

Growth Rate

Amazon Frogbit has a slow to the medium growth rate. Under the right conditions, they will grow faster but they will not grow super fast like duckweed. This makes it easy for you to control their population and maintain them.  

Because of their slow growth rate and their wide leaves, the light can reach the bottom of the tank making life possible for any submerged plants that you might have in your tank. However, they still have the potential to deprive your tank of oxygen by blocking the surface. This can cause your fish or other inhabitants to suffer if not taken care of. You can solve it by placing one or two air stones to create air bubbles and oxygenate the water. 

Amazon Frogbit Care

Amazon Frogbit care is easy. They can be kept in an aquarium with no special equipment or supplements. With the right tank temperature and the right type of light, this plant can grow beautifully.  

The most important thing to know about caring for this plant is to make sure the surface of the water doesn’t move. Amazon frogbits love still water and may not be able to survive if the tank has a lot of agitation. 

Tank Size

Amazon Frogbit can grow in any size aquarium. But because they have larger leaves you might need to have them in a tank that is 10 gallons or more. A tank of this size will provide them with enough surface to create a beautiful green carpet on the surface of the water. 

The volume of the tank does not matter that much as they just need the surface. So it is best to choose your tank for your fish or other inhabitants that you want to own. 

You might need to cut the roots of this plant if you have a tank with a short height. The roots will grow long close to 8 – 10 inches and can reach the bottom of a smaller tank. Cutting the roots will not harm the plant as long as you leave a few inches so the plant can absorb nutrition.  

Water Conditions

Amazon Frogbit needs a still surface of the water to be able to thrive. With the right light and water conditions, they will grow nicely on top of the water.

They need regular water changes to be able to get all the nutrition they need and to keep the pH of the tank stable. Fluctuating pH levels can cause the leaves to rot. Below is the ideal range of parameters your Amazon Frogbit can thrive. 

  • Water temperature: 64° – 86° degrees Fahrenheit 
  • pH levels: 6.0 to 7.5
  • Water hardness: 0 – 12 GH

CO2 Requirement

Amazon Frogbit do not need dissolved CO2 (carbon dioxide) in the water. The leaves grow out of the water and have access to the CO2 in the air. They will absorb carbon dioxide directly from the air.

Amazon Frogbit

Lighting

Amazon Frogbits need strong light to grow. When the light levels are low they tend to lose leaves more often and grow at a slower rate.

They also need a full spectrum light source to be able to easily photosynthesis. When you provide them with the right type of light and enough fertilizer available in the water, they will grow beautiful leaves and will have very few die-offs. 

Substrate

The good news is that Amazon Frogbit does not need substrates. They absorb the nutrition directly from the water column. This puts them in the category of water column plants even though they have a root structure that actively absorbs nutrition. 

Amazon Frogbit Propagation

In the wild, Amazon Frogbits propagate by spreading seeds as well as shooting runners. However, in an aquarium environment, it seems like they only propagate by shooting new runners. 

Once the mother plant establishes a strong root structure and the conditions are right, it will start to send out new stem-like runners and at the end of the runner, a new plant will grow. After some time the runner that connects the mother plant and the child plant will start to deteriorate in the water and the child plant will continue to grow on its own.

Maintenance 

Maintaining Amazon Frogbit is very straightforward. This plant is super easy-going and beginner friendly. They grow at a moderate rate which makes it easy to control their population in the tank. more on this below in the population control section of this guide.

Fertilization

With the right conditions and enough fish in the tank, the Amazon Frogbit will not need any fertilization. The fish waste is enough for them to be able to grow. 

If you have other plants that can compete with your amazon frogbits over nutrients you can supplement your tank with liquid fertilizers so all your plants can thrive. 

Population Control (pruning and trimming)

Because of its large size, the amazon frogbit plant is easy to manage. They grow large leaves that will die after some time so you might need to cut the dead leaves after some time.

Older leaves will slowly get yellowish and start to deteriorate. This is the sign you need to start pruning the plants. 

Dead leaves have the potential to pollute the water so it’s important to remove them one by one to maintain the clarity and clearness of the water in your tank. 

You will also need to remove some of the plants if they start to fill the tank completely. same time 

Tank Mates

Picking tank mates for amazon frogbits is easy as they can live with most plants and fish. Because amazon frogbits have a fine root structure that some fish might eat. 

This plant is ideal for shrimp tanks as it can fully grow its roots and the shrimps will appreciate the extra surface area and food this plant provides them. 

Larger herbivore fish or snails might try to eat your Amazon Frogbits so it is important to keep an eye on your plant for the first few weeks to see if they are thriving or not.

Here are our top picks of tank mates for Amazon Frogbits:

Is Amazon Frogbit Suitable for Your Aquarium?

The Amazon Frogbit plant is highly effective at filtering out harmful substances from water. Even though they are not growing at a high rate like duckweed, they still absorb a lot of fish waste from the tank as they grow large leaves. 

If your tank has slow-moving water with a still surface then this plant can be a great addition to your tank. They can reduce the amount of light reaching your decorations and thus can prevent algae growth.  

If you have other submerged live plants that need strong lighting, the Amazon Frogbit might not be an ideal plant to add to your tank. Amazon Frogbit will block the light on your sensitive plants and might cause suffering as a result. 

Hardy and low-light plants like anubias are ideal types of plants to keep with your amazon sponge plants. 

Amazon Frogbit

Conclusion

As you now know, Amazon Frogbit is a really simple and easy-to-care aquarium plant. They grow to a manageable size and make beautiful scenery both above and below the surface of the water. If your tank parameters and conditions match what we mentioned in this guide, then we highly recommend having this plant. 

If you have any unanswered questions, please contact us via email and we will happily help you with your questions.